ABSTRACT
-A prospective study was carried out in patients suffering from old peripheral nerve
and brachial plexus injuries to attempt to validate that functional improvement was
possible after microsurgical management. Fifty patients underwent operative procedures,
of whom 35 were peripheral-nerve injury cases, from 1.2 to 50 years after injury,
and 15 were brachial-plexus injury cases, from 1.2 to 12 years after injury. The patients
were treated by external and interfascicular neurolysis and/or autogenous nerve grafts.
In cases of preganglionic nerve injury, neurotization from C3, C4 roots was done for
reinnervation of trunks or cords. During external and interfascicular neurolysis in
19 of the 35 peripheral-nerve injuries, significant improvement was found in amplitude
(p = 0.0001) and latency (p = 0.01) of compound muscle action potentials (CMAPs) at
the end of the surgery, compared to the onset of surgery. Twenty (57 percent) of the
35 showed functional motor improvement up to M4- or M4. Electrophysiologic analysis
of amplitude of CMAPs 1 year after surgery showed statistically significant improvement
(p = 0.0003). Five (33 percent) of the 15 patients with upper brachial-plexus injuries
showed functional motor improvement up to M4- (active movements against gravity and
slight resistance) or M4 (active movements against gravity and moderate resistance)
after surgery and of these, 11 also had lower brachial-plexus injuries, with four
(36 percent) showing antigravity function M3 (active movement against gravity). Statistical
analysis of recruitment 1 year after surgery demonstrated the appearance of or significant
voluntary muscle activity in 45 percent of the muscles.
Intraoperative electrophysiologic findings after external and interfascicular neurolysis
confirmed that the viability of nerve tissue is of longer duration than previously
considered. This study suggests that the use of microsurgical techniques results in
the functional improvement of patients suffering from old injuries of the peripheral
nerve and brachial plexus.
